*{
    padding: 0;
    margin:0;
}
body{
    padding: 0;
    margin:0;
}
.main{
    -webkit-perspective:800;
    -webkit-perspective:-orinig;50% 50%;
    overflow: hidden;
}

.main .pageGround{
    width: 400px;
    height: 400px;
    margin:0 auto;

    -webkit-transform-style:preserve-3d;
    position: relative;
}

.main .pageGround .page{
    width: 360px;
    height: 360px;
    padding: 20px;
    background-color: black;
    color: white;
    font-size: 260px;
    text-align: center; 
    line-height: 360px;
    position:absolute;
    -webkit-transform-origin:bottom;
    -webkit-transition:-webkit-transform 1s linear;
    -webkit-transform:rotateX(90deg);
}
#page1
{
    -webkit-transform:rotateX(0deg);
}

#op{
    width: 400px;
    margin:0 auto;
    text-align: center;
}